diff --git a/lib/std/os/bits/linux/sparc64.zig b/lib/std/os/bits/linux/sparc64.zig
index ba2183acb13c30a49b873d3bc5062183f560d4c4..e216f8abaa97a77f6f47b52837bd14ecfed0dc8b 100644
--- a/lib/std/os/bits/linux/sparc64.zig
+++ b/lib/std/os/bits/linux/sparc64.zig
@@ -544,6 +544,9 @@ pub const timezone = extern struct {
     tz_dsttime: i32,
 };
 
+// TODO I'm not sure if the code below is correct, need someone with more
+// knowledge about sparc64 linux internals to look into.
+
 pub const Elf_Symndx = u32;
 
 pub const fpstate = extern struct {
diff --git a/lib/std/start.zig b/lib/std/start.zig
index 47164a082090a56709de090bdc9c2623d857ca00..dae8251d9aeb6dbaac7cd3abc3575b2ad6d25b66 100644
--- a/lib/std/start.zig
+++ b/lib/std/start.zig
@@ -147,6 +147,11 @@ fn _start() callconv(.Naked) noreturn {
                 : "r0"
             );
         },
+        .sparcv9 => {
+            starting_stack_ptr = asm (""
+                : [argc] "={o6}" (-> [*]usize)
+            );
+        },
         else => @compileError("unsupported arch"),
     }
     // If LLVM inlines stack variables into _start, they will overwrite